Reclassify data after loading IO class configuration

casadm/cas_lib.c

@@ -2707,7 +2707,7 @@ int partition_set_config(struct kcas_io_classes *cnfg)
 	return result;
 }
 
-int partition_setup(unsigned int cache_id, const char *file)
+int partition_setup(unsigned int cache_id, bool reclassify, const char *file)
 {
 	int result = 0;
 	CSVFILE *in;
@@ -2739,6 +2739,7 @@ int partition_setup(unsigned int cache_id, const char *file)
 	}
 
 	if (0 == partition_get_config(in, cnfg, cache_id)) {
+		cnfg->repart_all = reclassify;
 		result = partition_set_config(cnfg);
 	} else {
 		result = FAILURE;

casadm/cas_lib.h

@@ -1,6 +1,6 @@
 /*
 * Copyright(c) 2012-2022 Intel Corporation
-* Copyright(c) 2024 Huawei Technologies
+* Copyright(c) 2024-2025 Huawei Technologies
 * Copyright(c) 2026 Unvertical
 * SPDX-License-Identifier: BSD-3-Clause
 */
@@ -311,7 +311,7 @@ int flush_core(unsigned int cache_id, unsigned int core_id);
 int check_cache_device(const char *device_path);
 
 int partition_list(unsigned int cache_id, unsigned int output_format);
-int partition_setup(unsigned int cache_id, const char *file);
+int partition_setup(unsigned int cache_id, bool reclassify, const char *file);
 int partition_is_name_valid(const char *name);
 
 int cas_module_version(char *buff, int size);

casadm/cas_main.c

@@ -1528,6 +1528,7 @@ enum {
 
 	io_class_opt_cache_id,
 	io_class_opt_cache_file_load,
+	io_class_opt_keep_classification,
 	io_class_opt_output_format,
 
 	io_class_opt_io_class_id,
@@ -1585,6 +1586,14 @@ static cli_option io_class_params_options[] = {
 		.priv = (1 << io_class_opt_subcmd_configure)
 			| (1 << io_class_opt_flag_required)
 	},
+	[io_class_opt_keep_classification] = {
+		.short_name = 'k',
+		.long_name = "keep-classification",
+		.desc = "Prevents reclassification of data in IO classes with IDs matching previous configuration",
+		.args_count = 0,
+		.arg = NULL,
+		.priv = (1 << io_class_opt_subcmd_configure)
+	},
 	[io_class_opt_output_format] = {
 		.short_name = 'o',
 		.long_name = "output-format",
@@ -1650,6 +1659,7 @@ struct {
 	int io_class_id;
 	int cache_mode;
 	int io_class_prio;
+	bool reclassify;
 	int output_format;
 	uint32_t min;
 	uint32_t max;
@@ -1659,6 +1669,7 @@ struct {
 	.subcmd = io_class_opt_subcmd_unknown,
 	.cache_id = 0,
 	.file = "",
+	.reclassify = true,
 	.output_format = OUTPUT_FORMAT_DEFAULT
 };
 
@@ -1695,6 +1706,10 @@ int io_class_handle_option(char *opt, const char **arg)
 			return FAILURE;
 
 		io_class_params_options[io_class_opt_output_format].priv |=  (1 << io_class_opt_flag_set);
+	} else if (!strcmp(opt, "keep-classification")) {
+		io_class_params.reclassify = false;
+
+		io_class_params_options[io_class_opt_keep_classification].priv |=  (1 << io_class_opt_flag_set);
 	}
 
 	return 0;
@@ -1751,7 +1766,7 @@ int io_class_handle() {
 	switch (io_class_params.subcmd) {
 	case io_class_opt_subcmd_configure:
 		return partition_setup(io_class_params.cache_id,
-				io_class_params.file);
+				io_class_params.reclassify, io_class_params.file);
 	case io_class_opt_subcmd_list:
 		return partition_list(io_class_params.cache_id,
 				io_class_params.output_format);

casadm/casadm.8

@@ -568,6 +568,14 @@ Identifier of cache instance <1-16384>.
 .B -f, --file <FILE>
 Configuration file containing IO class definition.
 
+.TP
+.B -k, --keep-classification
+Keep classification of data cached in IO classes present in the new
+configuration. By default data of all the IO classes is moved to the
+unclassified IO class and gets classified again on next access. Data of IO
+classes removed from the configuration is reclassified regardless of this
+option.
+
 .SH Options that are valid with --io-class --list (-C -L) are:
 .TP
 .B -i, --cache-id <ID>

modules/cas_cache/layer_cache_management.c

@@ -1785,12 +1785,15 @@ int cache_mngt_set_partitions(const char *cache_name, size_t name_len,
 
 	for (class_id = 0; class_id < OCF_USER_IO_CLASS_MAX; class_id++) {
 		io_class_cfg->config[class_id].class_id = class_id;
+		/* Data of removed IO classes is always reclassified */
+		io_class_cfg->config[class_id].repart = true;
 
 		if (!cfg->info[class_id].name[0]) {
 			io_class_cfg->config[class_id].class_id = class_id;
 			continue;
 		}
 
+		io_class_cfg->config[class_id].repart = cfg->repart_all;
 		io_class_info2cfg(class_id, &cfg->info[class_id],
 				&io_class_cfg->config[class_id]);
 	}

modules/include/cas_ioctl_codes.h

@@ -258,6 +258,9 @@ struct kcas_io_classes {
 	/** Cache ID */
 	uint16_t cache_id;
 
+	/** Reclassify data of all IO classes, not only of the removed ones */
+	bool repart_all;
+
 	int ext_err_code;
 
 	/** IO class info */

test/functional/api/cas/cache.py

@@ -1,6 +1,7 @@
 #
 # Copyright(c) 2019-2021 Intel Corporation
 # Copyright(c) 2024-2026 Huawei Technologies Co., Ltd.
+# Copyright(c) 2026 Unvertical
 # SPDX-License-Identifier: BSD-3-Clause
 #
 
@@ -174,8 +175,10 @@ def reset_counters(self) -> Output:
     def set_cache_mode(self, cache_mode: CacheMode, flush=None) -> Output:
         return casadm.set_cache_mode(cache_mode, self.cache_id, flush)
 
-    def load_io_class(self, file_path: str) -> Output:
-        return casadm.load_io_classes(self.cache_id, file_path)
+    def load_io_class(self, file_path: str, keep_classification: bool = False) -> Output:
+        return casadm.load_io_classes(
+            self.cache_id, file_path, keep_classification=keep_classification
+        )
 
     def list_io_classes(self) -> list:
         return get_io_class_list(self.cache_id)

test/functional/api/cas/casadm.py

@@ -1,6 +1,7 @@
 #
 # Copyright(c) 2019-2022 Intel Corporation
 # Copyright(c) 2024-2026 Huawei Technologies Co., Ltd.
+# Copyright(c) 2026 Unvertical
 # SPDX-License-Identifier: BSD-3-Clause
 #
 
@@ -589,9 +590,16 @@ def flush_core(cache_id: int, core_id: int, shortcut: bool = False) -> Output:
     return output
 
 
-def load_io_classes(cache_id: int, file: str, shortcut: bool = False) -> Output:
+def load_io_classes(
+    cache_id: int, file: str, shortcut: bool = False, keep_classification: bool = False
+) -> Output:
     output = TestRun.executor.run(
-        load_io_classes_cmd(cache_id=str(cache_id), file=file, shortcut=shortcut)
+        load_io_classes_cmd(
+            cache_id=str(cache_id),
+            file=file,
+            shortcut=shortcut,
+            keep_classification=keep_classification,
+        )
     )
     if output.exit_code != 0:
         raise CmdException("Load IO class command failed.", output)

test/functional/api/cas/cli.py

@@ -411,10 +411,14 @@ def flush_core_cmd(cache_id: str, core_id: str, shortcut: bool = False) -> str:
     return casadm_bin + command
 
 
-def load_io_classes_cmd(cache_id: str, file: str, shortcut: bool = False) -> str:
+def load_io_classes_cmd(
+    cache_id: str, file: str, shortcut: bool = False, keep_classification: bool = False
+) -> str:
     command = " -C -C" if shortcut else " --io-class --load-config"
     command += (" -i " if shortcut else " --cache-id ") + cache_id
     command += (" -f " if shortcut else " --file ") + file
+    if keep_classification:
+        command += (" -k" if shortcut else " --keep-classification")
     return casadm_bin + command
 
 

test/functional/api/cas/cli_help_messages.py

@@ -297,6 +297,7 @@
     r"Options that are valid with --load-config \(-C\) are:",
     r"-i  --cache-id \<ID\>                  Identifier of cache instance \<1-16384\>",
     r"-f  --file \<FILE\>                    Configuration file containing IO class definition",
+    r"-k  --keep-classification            Prevents reclassification of data in IO classes with IDs matching previous configuration",
     r"Lists currently configured IO classes:",
     r"Usage: casadm --io-class --list --cache-id \<ID\> \[option\.\.\.\]",
     r"Options that are valid with --list \(-L\) are:",

test/functional/api/cas/ioclass_config.py

@@ -160,6 +160,8 @@ def generate_random_ioclass_list(count: int, max_priority: int = MAX_IO_CLASS_PR
             ),
         ]
         for i in range(1, count - 1):
+            if random.choice([True, False]):
+                continue
             random_list.append(
                 IoClass(
                     i,

test/functional/tests/io_class/io_class_common.py

@@ -92,10 +92,12 @@ def get_io_class_usage(cache, io_class_id, percent=False):
     ).usage_stats
 
 
-def generate_and_load_random_io_class_config(cache):
+def generate_and_load_random_io_class_config(cache, keep_classification=False):
     random_list = IoClass.generate_random_ioclass_list(ioclass_config.MAX_IO_CLASS_ID + 1)
     IoClass.save_list_to_config_file(random_list, add_default_rule=False)
-    cache.load_io_class(ioclass_config.default_config_file_path)
+    cache.load_io_class(
+        ioclass_config.default_config_file_path, keep_classification=keep_classification
+    )
     return random_list
 
 

test/functional/tests/io_class/test_io_class_cli.py

@@ -47,7 +47,7 @@ def test_io_class_export_configuration():
             )
 
     with TestRun.LOGGER.step(
-        "Create and load configuration file for 33 IO classes "
+        "Create and load random configuration file for up to 33 IO classes "
         "with random names, allocation and priority values"
     ):
         random_list = IoClass.generate_random_ioclass_list(33)

test/functional/tests/io_class/test_io_class_eviction_pinned_after_unpin.py

@@ -65,7 +65,7 @@ def test_io_class_eviction_pinned_after_unpin():
 
     with TestRun.step("Unpin ioclass to and set its priority to be lower than second IO class"):
         io_classes = [IoclassConfig(1, 11, 1, cores[0]), IoclassConfig(2, 10, 1, cores[1])]
-        _add_and_load_io_classes(cache.cache_id, io_classes)
+        _add_and_load_io_classes(cache.cache_id, io_classes, keep_classification=True)
 
     with TestRun.step("Run dd on second io ioclass "):
         run_io_dir(f"{io_classes[1].core.path}", usable_cache_size)
@@ -89,7 +89,7 @@ def _refresh_cache(cache):
     cache.reset_counters()
 
 
-def _add_and_load_io_classes(cache_id, io_classes: list):
+def _add_and_load_io_classes(cache_id, io_classes: list, keep_classification=False):
     ioclass_config.remove_ioclass_config()
     ioclass_config.create_ioclass_config(False)
 
@@ -102,7 +102,11 @@ def _add_and_load_io_classes(cache_id, io_classes: list):
             ioclass_config_path=ioclass_config.default_config_file_path,
         )
 
-    casadm.load_io_classes(cache_id=cache_id, file=default_config_file_path)
+    casadm.load_io_classes(
+        cache_id=cache_id,
+        file=default_config_file_path,
+        keep_classification=keep_classification,
+    )
 
 
 def prepare(cores_number=1, cache_size=Size(10, Unit.GibiByte), core_size=Size(5, Unit.GibiByte)):

test/functional/tests/io_class/test_io_class_occupancy_resize.py

@@ -138,7 +138,11 @@ def test_ioclass_resize(cache_line_size, new_occupancy):
             f"{io_class.max_occupancy:0.2f}",
         )
 
-        casadm.load_io_classes(cache_id=cache.cache_id, file=default_config_file_path)
+        casadm.load_io_classes(
+            cache_id=cache.cache_id,
+            file=default_config_file_path,
+            keep_classification=True,
+        )
 
     with TestRun.step("Perform IO with size equal to cache size"):
         run_io_dir(f"{io_class.dir_path}/tmp_file", cache_size)

test/functional/tests/io_class/test_io_class_preserve_config.py

@@ -52,7 +52,7 @@ def test_io_class_preserve_configuration():
         cache.add_core(core_device)
 
     with TestRun.step(
-        "Create and load configuration file for all IO classes with random names, "
+        "Create and load random configuration file with random names, "
         "allocation and priority values."
     ):
         generated_io_classes = generate_and_load_random_io_class_config(cache)